This invention relates to a flyback transformer for supplying a DC high voltage to a cathode-ray tube at a television receiver or the like, and more particularly to a flyback transformer having an improved construction to mount to coil bobbin diodes connected to the secondary windings.
Recently, various flyback transformers of the so-called diode-split type have been proposed which, as shown in the equivalent circuit in FIG. 1, comprise a plurality of split secondary windings 12, 13, 14 which are magnetically coupled to the primary winding 11 and a plurality of diodes 15, 16, 17 connected alternately in series to respective primary windings.
Such flyback transformers each are so constructed that a secondary winding bobbin is provided with a plurality of flanges, a plurality of coil winding grooves, and a plurality of diode insertion grooves, so that secondary windings are wound into the coil winding grooves and diodes are disposed into the diode insertion grooves, respectively.
Conventionally, several mounting means have been adopted to dispose the diodes into the diode insertion grooves, two different examples of which are shown in FIGS. 2 and 3.
Referring at first to FIG. 2, a pair of supports 20, 21 having upper cutouts 18, 19, respectively, are formed integrally with the diode insertion groove at the secondary winding bobbin, and a diode 22 is inserted with its lead wires 23 being placed into the cutouts 18, 19. Thereafter the supports 20, 21 are fused in the vicinity of cutouts 18, 19, so as to prevent the diode 22 from escaping.
Next, in FIG. 3, at the diode insertion groove at the secondary winding bobbin are formed a pair of supports 26, 27 providing upper terminal pins 24, 25 and integral with the bobbin, the terminal pins 24, 25 being wound with lead wires 23 of the diode 22 and soldered at the winding portions, thereby fixing lead wires 23 to the pins 24, 25, respectively.
In the mounting means in FIG. 2, the fusion of support can prevent the diode 22 from escaping, but the diode is not fixed to the supports, thereby making it difficult to connect the lead wires to terminals of secondary winding due to rolling or laterally shifting of the diode 22.
The mounting means shown in FIG. 3 requires a surplus work of attaching the terminal pins to the supports and the diode lead wires should be wound around the terminal pins which results in inconvenience of complicated work.
Furthermore, the connection process of each of the foregoing structures are difficult to automate.
In addition, other various means have been proposed, which are defective similarly to the above.